This application claims the priority of German application 199 21 825.0, filed in Germany on May 11, 1999, the disclosure of which is expressly incorporated by reference herein.
The invention relates to a display device to display selected speeds and ratios.
A display device according to the species is known for example from European Patent Document EP 0 361 011 A1. This display device for an automatic vehicle transmission comprises, in addition to first display elements to display a preselected speed, second display elements. The second display elements, especially in a semiautomatic operating mode of the motor vehicle transmission with manual selection of the speeds, make a speed just engaged visually recognizable. The first and second display elements are advantageously arranged in two parallel vertical rows in a display instrument of the motor vehicle.
The disadvantage of this known display device is that it occupies additional space in the display instrument.
By contrast with this prior art, a goal of the invention is to provide a display device of the above noted type in which the space requirement for the display is reduced.
This goal is achieved according to the invention by providing a display device for a motor vehicle transmission for displaying selected speeds and/or ratios characterized in that scale elements of a display instrument are used as display elements.
According to the invention it is proposed to use as display elements scale elements such as scale numbers or divisions of a display instrument. Since these scale elements are present in any event, the display device requires little if any additional area to display the selected speeds depending on whether all the speeds or gears can be represented by the existing scale numbers.
Advantageous improvements on the invention are described below and in the claims.
Thus, it is proposed to use a tachometer as the display instrument in certain preferred embodiments. The scale numbers of a tachometer are especially suitable as a display element to display speeds since all of the necessary numbers are already present in correct order. In addition, the tachometer as the central display instrument is located mostly in the immediate visual field of the driver so that the selected speeds can be displayed especially clearly. The lines of the scale divisions can be used to display the selected ratio, for example in conjunction with a continuously variable transmission.
As is also proposed according to certain preferred embodiments, the display device can be created by individual scale numbers being provided with transparent illumination for use as display elements. To display the selected speed, the corresponding scale number is illuminated from behind and appears to the driver to be lighter than the other scale numbers not used. In order to make the active display element stand out from the non-active display elements even when the instrument illumination is switched on, it is finally proposed to select a different color than the instrument illumination for the transparent illumination. In this way, the active display element can be distinguished clearly when driving either in the day or at night. In particular, it is also possible to combine the display elements with instrument illumination designed as transparent illumination.
Other advantages, features, and details of the invention will be found in the description below in which a number of embodiments of the invention are described in detail with and the specification may be important to the invention individually or in any combination.